Gabbroic xenoliths in alkaline lavas in the region of Sanganguey Volcano, Nayarit, Mexico
Abstract
Gabbroic xenoliths occur in alkaline cinder cones and lava flows erupted from vents along five parallel lines trending through the calc-alkaline volcano, Sanganguey in the northwestern portion of the Mexican Volcanic Belt. The xenoliths consist of varying proportions of olivine, clinopyroxene, orthopyroxene, and plagioclase. The complete lack of hydrous phases indicates that the gabbros crystallized under conditions of low PH/sub 2/O. Many xenoliths show textures indicative of a cumulate origin and others exhibit recrystallization indicative of subsolidus reactions prior to incorporation in the host liquids. Reaction between xenolithic minerals and host liquids are also observed. The range of Mg numbers calculated for liquids that would have been in equilibrium with olivines in the xenoliths suggests that these olivines crystallized from magmas such as those represented by either calc-alkaline basaltic andesites and andesites or the more evolved alkalic rocks which occur throughout the area. Crystal fractionation models show that the xenoliths may be related to such magmas. The fact that xenoliths occur most commonly in the alkaline rocks suggests that alkaline magmas rise to the surface more rapidly than the more chemically evolved calc-alkaline and alkaline magmas. Alternatively the lack of xenoliths in the more evolved magmas produced by high levelmore »
- Authors:
- Publication Date:
- Research Org.:
- Tulane Univ., New Orleans, LA (USA)
- OSTI Identifier:
- 6596723
- Report Number(s):
- CONF-8510489-
Journal ID: CODEN: GAAPB
- Resource Type:
- Conference
- Journal Name:
- Geol. Soc. Am., Abstr. Programs; (United States)
- Additional Journal Information:
- Journal Volume: 17; Conference: 98. annual meeting of the Geological Society of America, Orlando, FL, USA, 28 Oct 1985
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 58 GEOSCIENCES; GABBROS; INCLUSIONS; PETROGENESIS; CHEMICAL COMPOSITION; MINERALOGY; MEXICO; CRYSTALLIZATION; GEOCHEMISTRY; GEOLOGIC MODELS; LAVA; MAGMATISM; VOLCANOES; CHEMISTRY; DEVELOPING COUNTRIES; IGNEOUS ROCKS; LATIN AMERICA; NORTH AMERICA; PHASE TRANSFORMATIONS; PLUTONIC ROCKS; ROCKS; 580300* - Mineralogy, Petrology, & Rock Mechanics- (-1989); 580400 - Geochemistry- (-1989)
Citation Formats
Giosa, T A, and Nelson, S A. Gabbroic xenoliths in alkaline lavas in the region of Sanganguey Volcano, Nayarit, Mexico. United States: N. p., 1985.
Web.
Giosa, T A, & Nelson, S A. Gabbroic xenoliths in alkaline lavas in the region of Sanganguey Volcano, Nayarit, Mexico. United States.
Giosa, T A, and Nelson, S A. 1985.
"Gabbroic xenoliths in alkaline lavas in the region of Sanganguey Volcano, Nayarit, Mexico". United States.
@article{osti_6596723,
title = {Gabbroic xenoliths in alkaline lavas in the region of Sanganguey Volcano, Nayarit, Mexico},
author = {Giosa, T A and Nelson, S A},
abstractNote = {Gabbroic xenoliths occur in alkaline cinder cones and lava flows erupted from vents along five parallel lines trending through the calc-alkaline volcano, Sanganguey in the northwestern portion of the Mexican Volcanic Belt. The xenoliths consist of varying proportions of olivine, clinopyroxene, orthopyroxene, and plagioclase. The complete lack of hydrous phases indicates that the gabbros crystallized under conditions of low PH/sub 2/O. Many xenoliths show textures indicative of a cumulate origin and others exhibit recrystallization indicative of subsolidus reactions prior to incorporation in the host liquids. Reaction between xenolithic minerals and host liquids are also observed. The range of Mg numbers calculated for liquids that would have been in equilibrium with olivines in the xenoliths suggests that these olivines crystallized from magmas such as those represented by either calc-alkaline basaltic andesites and andesites or the more evolved alkalic rocks which occur throughout the area. Crystal fractionation models show that the xenoliths may be related to such magmas. The fact that xenoliths occur most commonly in the alkaline rocks suggests that alkaline magmas rise to the surface more rapidly than the more chemically evolved calc-alkaline and alkaline magmas. Alternatively the lack of xenoliths in the more evolved magmas produced by high level crystal fractionation may indicate that the xenoliths are derived from zones below that from which the differentiated magmas begin their final ascent to the surface.},
doi = {},
url = {https://www.osti.gov/biblio/6596723},
journal = {Geol. Soc. Am., Abstr. Programs; (United States)},
number = ,
volume = 17,
place = {United States},
year = {Tue Jan 01 00:00:00 EST 1985},
month = {Tue Jan 01 00:00:00 EST 1985}
}